There has always been a gray zone between peace and war, but never have nations tried to exploit this fact as much as today. Nations use the cognitive and legal spaces between peace and war to their advantage, with the purpose of achieving political and military goals. While this fact broadens the spectrum of war, it also challenges existing laws, regulating when and how militaries can use deadly force. The sea has been part of several recent gray zone conflicts, primarily involving Russia and China. The successes this type of warfare has achieved, makes it likely these nations will continue on the same path in the future.   The purpose of this paper is to answer in what way Swedish law restricts the Swedish Navy tactically in a gray zone conflict. This is done through a case study involving a fictive case by the Swedish Defence Research Agency, creating a plausible gray zone scenario in Sweden and the Baltic Sea Region. Additions are made to the case to aim the focus on the maritime domain. Law regulating when the Swedish Navy can use force, is triangulated with part of Wayne P. Hughes’s theory, Six cornerstones. The part used to analyze the case is the sixth cornerstone, Attack effectively first, which emphasizes the importance of attacking first in order to achieve tactical success at sea.   The analysis concludes that Swedish law puts the Swedish Navy in a severe tactical disadvantage, in a gray zone conflict, by restricting the use of force against non-military vessels. Because of that, Swedish ships will always be second to fire, preventing the possibility of attacking effectively first.